The increasing use of the polymerase chain reaction (PCR) for diagnosis of infectious diseases has resulted in a need for better methods for detecting and quantitating products of PCR reactions. The DELFIA time- resolved fluorometric system produced by Wallac Inc., based on the use of inherently fluorescent lanthanide chelates as probe labels, enables quantitative detection of DNA hybridization complexes in a highly sensitive and specific manner. Our aim is to use DELFIA as our primary system for PCR product detection in diagnostic PCR-based assays currently being developed in the Microbiology Service. We will construct universal control amplicons via the PCR-MIMIC technique developed by Clontech Inc. for the pathogens of interest (currently CMV, HSV, VZV, M.tuberculosis, Mycobacterium sp., M. avium) and then develop assays for simultaneous detection of the target and control DNA via use of the DELFIA system. This will enable us to have internal controls in each reaction, and will also give us the potential for developing quantitative competitive (QC-PCR) assays for more accurate estimation of the quantity of an infectious agent in a give specimen. We intend to demonstrate the feasibility and clinical utility of this approach by developing such an assay for the quantitative detection of CMV in blood (both buffy coat and serum).